package com.lcx.client;

import com.lcx.encoder.RpcDecoder;
import com.lcx.encoder.RpcEncoder;
import com.lcx.handler.UserClientHandler;
import com.lcx.request.RpcRequest;
import com.lcx.serializer.JSONSerializer;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

/**
 * 消费端
 */
public class RPCConsumer{

    //1、创建一个线程池对象 --它要处理我们自定义事件
    private static ExecutorService executorService =
            Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());

    //2.声明一个自定义事件处理器，UserClientHandler
    private static UserClientHandler userClientHandler;

    //3.初始化客户端（创建连接池，设置boostrap，连接服务器）
    public static void init() throws InterruptedException {
        //1)初始化userClientHandler
        userClientHandler = new UserClientHandler();
        //2)创建连接池对象
        NioEventLoopGroup group = new NioEventLoopGroup();
        //3)创建客户端的引导对象
        Bootstrap bootstrap = new Bootstrap();
        //4)配置启动引导对象
        bootstrap.group(group)
                .channel(NioSocketChannel.class)
                //设置请求协议为TCP
                .option(ChannelOption.TCP_NODELAY,true)
                .handler(new ChannelInitializer<SocketChannel>() {
                    @Override
                    protected void initChannel(SocketChannel socketChannel) throws Exception {
                        ChannelPipeline pipeline = socketChannel.pipeline();
                        pipeline.addFirst(new RpcEncoder(RpcRequest.class,new JSONSerializer()));
                        pipeline.addLast(new StringDecoder());
                        pipeline.addLast(userClientHandler);
                    }
                });
        //5）连接服务器
        bootstrap.connect("127.0.0.1",8999).sync();
    }

    //4、使用jdk动态代理创建对象
    //serviceClass 根据接口生成子类代理对象， providerParam ： “UserService#sayHello”
    public static Object createProxy(Class<?> serviceClass,RpcRequest re){
        return Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(),
                new Class[]{serviceClass}, new InvocationHandler() {
                    @Override
                    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                        //1)初始化客户端client
                        if (userClientHandler == null){
                            init();
                        }
                        //设置参数
                        re.setClassName(method.getDeclaringClass().getName());
                        re.setMethodName(method.getName());
                        re.setParameters(args);
                        re.setParameterTypes(method.getParameterTypes());
                        //2)给UserClientHandler设置参数
                        //userClientHandler.setParam(providerParam+args[0]);
                        userClientHandler.setRequest(re);
                        //3)使用线程池开启一个线程处理call()写操作，返回结果
                        Object result = executorService.submit(userClientHandler).get();
                        return result;
                    }
                });
    }
}
